BUILDS and flashers, hell knows what's going on?

I have ata/100 maxtor HDD, 7200rpm, and ASUS A7V, previously before flashing the mobo and loading to Windows it showed me Promise BIOS and it said BUILD 28 in parentheses, after updating to 1008 BIOS I have BUILD 39 in parentheses and it suppose to be better (what does it al mean? amount of HDD's it can recognize or what?) and also ASUS has a driver for Promise ata/100 HDDs and it is BUILD33 but shouldn't that decrease the performance?(remeber it says BUILD 39 in promise BIOS), Promise website has BUILD27 driver and it is even worse, I can't find BUILD 39 driver! It does matter to me, cuz there is a big performance increasing from BUILD 28 to BIULD 33 (drivers, not BIOS) ??? and what are MASTER BUS drivers? are they included in 4in1 drivers?